Disable computed var deps (#872)

pynecone/state.py

@@ -673,15 +673,23 @@ class State(Base, ABC, extra=pydantic.Extra.allow):
         # Return the state update.
         return StateUpdate(delta=delta, events=events)
 
-    def _dirty_computed_vars(self, from_vars: Optional[Set[str]] = None) -> Set[str]:
+    def _dirty_computed_vars(
+        self, from_vars: Optional[Set[str]] = None, check: bool = False
+    ) -> Set[str]:
         """Get ComputedVars that need to be recomputed based on dirty_vars.
 
         Args:
             from_vars: find ComputedVar that depend on this set of vars. If unspecified, will use the dirty_vars.
+            check: Whether to perform the check.
 
         Returns:
             Set of computed vars to include in the delta.
         """
+        # If checking is disabled, return all computed vars.
+        if not check:
+            return set(self.computed_vars)
+
+        # Return only the computed vars that depend on the dirty vars.
         return set(
             cvar
             for dirty_var in from_vars or self.dirty_vars
@@ -689,9 +697,12 @@ class State(Base, ABC, extra=pydantic.Extra.allow):
             if cvar in self.computed_var_dependencies.get(dirty_var, set())
         )
 
-    def get_delta(self) -> Delta:
+    def get_delta(self, check: bool = False) -> Delta:
         """Get the delta for the state.
 
+        Args:
+            check: Whether to check for dirty computed vars.
+
         Returns:
             The delta for the state.
         """
@@ -700,7 +711,7 @@ class State(Base, ABC, extra=pydantic.Extra.allow):
         # Return the dirty vars, as well as computed vars depending on dirty vars.
         subdelta = {
             prop: getattr(self, prop)
-            for prop in self.dirty_vars | self._dirty_computed_vars()
+            for prop in self.dirty_vars | self._dirty_computed_vars(check=check)
             if not types.is_backend_variable(prop)
         }
         if len(subdelta) > 0:

tests/test_state.py

@@ -578,7 +578,7 @@ async def test_process_event_simple(test_state):
     assert test_state.num1 == 69
 
     # The delta should contain the changes, including computed vars.
-    assert update.delta == {"test_state": {"num1": 69, "sum": 72.14}}
+    assert update.delta == {"test_state": {"num1": 69, "sum": 72.14, "upper": ""}}
     assert update.events == []
 
 
@@ -601,6 +601,7 @@ async def test_process_event_substate(test_state, child_state, grandchild_state)
     assert child_state.value == "HI"
     assert child_state.count == 24
     assert update.delta == {
+        "test_state": {"sum": 3.14, "upper": ""},
         "test_state.child_state": {"value": "HI", "count": 24},
     }
     test_state.clean()
@@ -615,6 +616,7 @@ async def test_process_event_substate(test_state, child_state, grandchild_state)
     update = await test_state._process(event)
     assert grandchild_state.value2 == "new"
     assert update.delta == {
+        "test_state": {"sum": 3.14, "upper": ""},
         "test_state.child_state.grandchild_state": {"value2": "new"},
     }
 
@@ -783,7 +785,7 @@ def test_not_dirty_computed_var_from_var(interdependent_state):
         interdependent_state: A state with varying Var dependencies.
     """
     interdependent_state.x = 5
-    assert interdependent_state.get_delta() == {
+    assert interdependent_state.get_delta(check=True) == {
         interdependent_state.get_full_name(): {"x": 5},
     }
 
@@ -798,7 +800,7 @@ def test_dirty_computed_var_from_var(interdependent_state):
         interdependent_state: A state with varying Var dependencies.
     """
     interdependent_state.v1 = 1
-    assert interdependent_state.get_delta() == {
+    assert interdependent_state.get_delta(check=True) == {
         interdependent_state.get_full_name(): {"v1": 1, "v1x2": 2, "v1x2x2": 4},
     }
 
@@ -810,12 +812,14 @@ def test_dirty_computed_var_from_backend_var(interdependent_state):
         interdependent_state: A state with varying Var dependencies.
     """
     interdependent_state._v2 = 2
-    assert interdependent_state.get_delta() == {
+    assert interdependent_state.get_delta(check=True) == {
         interdependent_state.get_full_name(): {"v2x2": 4},
     }
 
 
 def test_child_state():
+    """Test that the child state computed vars can reference parent state vars."""
+
     class MainState(State):
         v: int = 2
 
@@ -829,3 +833,24 @@ def test_child_state():
     assert ms.v == 2
     assert cs.v == 2
     assert cs.rendered_var == 2
+
+
+def test_conditional_computed_vars():
+    """Test that computed vars can have conditionals."""
+
+    class MainState(State):
+        flag: bool = False
+        t1: str = "a"
+        t2: str = "b"
+
+        @ComputedVar
+        def rendered_var(self) -> str:
+            if self.flag:
+                return self.t1
+            return self.t2
+
+    ms = MainState()
+    # Initially there are no dirty computed vars.
+    assert ms._dirty_computed_vars(from_vars={"flag"}) == {"rendered_var"}
+    assert ms._dirty_computed_vars(from_vars={"t2"}) == {"rendered_var"}
+    assert ms._dirty_computed_vars(from_vars={"t1"}) == {"rendered_var"}